The US Food and Drug Administration (FDA) has granted clearance for GT Biopharma’s investigational new drug (IND) application for the commencement of a Phase I clinical trial of GTB-3650 to treat CD33+ leukaemia.
The Phase I dose escalation trial of the natural killer (NK) cell engager is projected to commence in the second half of this year.
It will evaluate GTB-3650 in up to six cohorts of adult CD33+ leukaemia patients.
Participants will include those with relapsed or refractory (r/r) CD33 expressing hematologic malignancies, including acute myeloid leukaemia (AML) and high-risk myelodysplastic syndrome (MDS).
They will receive GTB-3650 in two-week cycles, alternating between treatment and rest periods over a maximum of four months, contingent on clinical outcomes.
The trial aims to evaluate several critical aspects, including the safety profile, pharmacokinetics, pharmacodynamics, the in vivo expansion of endogenous patient NK cells, and the overall clinical activity of the treatment.
With the Phase I trial of GTB-3650 on the horizon, multiple data readouts are anticipated throughout 2025.
In addition to GTB-3650, GT Biopharma is preparing for the submission of an IND application for GTB-5550 TriKE, targeting B7H3 positive solid tumours, expected in the first quarter of next year.
A Phase I dose escalation basket trial, anticipated for initiation in 2025, will assess GTB-5550 across six types of solid tumour cancers, including prostate, breast, head and neck, ovarian, lung, and gastrointestinal (GI) cancers.
The company has also projected that its current cash reserves should be adequate to finance its operations well into 2025.
GT Biopharma executive chairman and interim CEO Michael Breen said: “GTB-3650 is designed to target NK cells within the immune system to potentially overcome many of the limitations of current AML chemotherapies.
“Our trial design should give us an early read on safety and potential therapeutic activity and also provide valuable learnings that we can translate into our clinical development plans for follow-on TriKE molecules, including GTB-5550.”